NAPLES, Fla. — At the end of his tour of Cambridge Christian School, a private academy in northwest Tampa, first-grader Giovanni Scanio had a question.

“How long will the school be open?” Giovanni asked, according to his mother, Lisa.

Giovanni wanted to know because a few weeks earlier, in July 2012, the charter school he loved abruptly shut down.

After just two years in operation, A.T. Jones Math, Science & Technology Academy had fallen about $121,000 into debt. The charter’s governing board members kept promising parents that a private investor would pump $100,000 into the school, but when the money never materialized, A.T. Jones became yet another charter casualty.